A celestial body that orbits a planet
Moon
A distinctive pattern in the night sky formed by a group of stars; the pattern often looks like a familiar object, such as an animal
Constellation
A space vehicle carrying scientific instruments and sent to fly past, orbit, or land on a celestial body to collect data
Probe
A theory representing the Sun as the centre of the universe.
Heliocentric
A natural object in space, such as the Sun, the Moon, a planet, or a star
Celestial Body
An enormous collection of gases, dust, and billions of stars held together by gravity
Galaxy
An apparent switch in the motion of a celestial body from eastward to westward motion, or vice versa, as viewed from Earth
Retrograde Motion
An electronic device put in orbit around Earth to relay information
Satellite
States that the universe is closed and will go through a series of expansions and contractions, or Big Bangs and Big Crunches, in an ongoing cycle
Oscillating Theory
The outermost part of the Sun’s atmosphere, a layer of gas that can reach more than 3 000 000°C
Corona
A rocky clump with a diameter of approximately 1 km or more that may eventually come together with other rocky clumps to form a planet
Planetesimal
A star pattern that is not a constellation; may consist of a small group of stars within a constellation or individual stars from different constellations
Asterism
A small, sophisticated, robotic probe designed to land on a planet, explore and test the surface, and send information back to Earth
Rover
The theory that proposes that the universe formed approximately 13.7 billion years ago when an unimaginably tiny volume of space suddenly and rapidly expanded to immense size
Big Bang Theory
A celestial body of hot gases with a nuclear furnace at its core that makes its own thermal energy
Star
A cloud of gas and dust in space
Nebula
A constellation that never appears to “set”, or dip below the horizon; this classification depends on the position of the viewer
Circumpolar Constellation
An instrument that gathers and focusses light or other types of electromagnetic radiation to magnify distant objects
Telescope
A dramatic, massive explosion that occurs when a large, high mass star collapses in on itself
Supernova
An optical instrument that uses one or more curved mirrors to gather and focus light from distant objects, forming a magnified image
Reflecting Telescope
A celestial body that orbits one or more stars, is large enough that its own gravity holds it in a spherical shape, and is the only body occupying the orbital path
Planet
The passage of a planet between the Earth and the Sun
Transit
An ancient instrument used to locate and predict the positions of the Sun, Moon, planets, and stars
Astrolabe
The regular path of an object, such as a celestial body or an artificial satellite, around another body such as a star or a planet
Orbit
Large loops of super-hot gas that extend out from the Sun’s surface
Solar Prominences